A: Whether you have a traditional goldfish in your pond or one of the many fancy varieties, you may notice their colors change over time – don’t worry. It doesn’t necessarily mean your fish have some sort of disease! In most cases, it’s normal for goldfish to change color. So before you start dumping antibiotics in your pond, first consider these possibilities:

Genetics

Goldfish naturally change color as they age. Though most do so during their first year or two of life, others change throughout their lifetime. Fish experts have identified two different types of color changes in fish: physiological and morphological.

Physiological changes occur when the pigments in the cells either spread out, which makes the colors more pronounced, or when the pigment clusters in the center, which makes the colors more muted. Morphological changes occur when the actual number of pigments in the cells increase or decrease. An example of a morphological change is when a black goldfish starts to turn orange or a young goldfish loses its black markings as it ages. In this case, as the fish matures, it’s losing its black pigment cells.

How and when their colors change really depends upon their individual genetic makeup. Inexpensive goldfish whose parents are unknown can change in unpredictable ways, while expensive show-quality fish will be a bit more predictable.

Keep in mind, however, that some of these color-enhancers may affect other colors, too. White areas on calico orandas, for instance, may take on an orange hue – which may not be the look you’re going for.

Illness, Poor Water Quality

If your goldfish’s color becomes very dull or it starts to become inactive, that could be a sign of illness or poor water quality. Use a test kit, like the Pond Master Test Kit, to check your water quality, including your pH, ammonia and nitrite levels. Then, if necessary, add a broad-spectrum medication, like Pond Care’s Melafix or Pimafix, to treat parasites or bacterial infections your fish may have.

27 Responses

hi Im not very experienced with the fancy goldfish cause i started when i was 14 yrs n now im gonna be 16 soon so not much experience .last week i bought 4 fancy goldfish 2 gold vieltail and 2 calico their about 2 inches in size.one of the calico got followed alot by one viel tail.im not sure its mating or bullying. the calico which was mostly white with other spots is some how looking red .it has no fin or tail rips n no missing scales. just worried about it.

Hi Hamza – The best you can do is to continue to monitor your fish. If there are changes in behavior you can test the water quality, increase oxygen through aeration, and also add Stress Reducer to help build the fish’s slime coat.

Hi Jennifer – Color change is not really an indicator of sex. Color change has more to do with environment and growth of the fish. If you are interested in finding out if your fish are male or female you will need to look closer at their body structure. Males tend to have a more slender body while females more rounded. Watch next spring and find that fish doing the chasing will be male, and the fish being chased are female. Here is an article on determining gender. While this is geared towards koi many of the same traits are used for determining gender in goldfish.

Hi Ashley – It is not uncommon for fish to change color, just make sure you have good filtration and are feeding them a balanced diet. You may want to read though our learning center for more fish care tips but feel free to contact us or e-mail pondhelp@thepondguy.com with more questions.

I have an apricot blush goldfish in an outdoor ornamental pond. Back in April, I thought a raccoon got it because it totally disappeared -nothing but orange, orange/white, orange/black and calicos in the pond, including over a complete cleanout where I saw every fish individually. Now, 3 months later I suddenly have a blush fish again. Is it possible it changed colors because it was carrying eggs?

Hi Janet – The biggest reason for color changes is stress or genetics. If a predator did visit your pond, the fish may have changed due to the stress of the incident. It’s hard to be 100% certain when it comes to color changes.

Hmmm. I did have to add about 6 to 7 inches of water to my pond a few days ago- maybe enough city water to affect the pH? I’ve long known that goldfish colors change with age, but have never seen one change overnight like this blush goldfish. I’ll have to keep an eye on it and see if it happens again- evaporation is a big problem when the temps are over 100 degrees most of the day and it doesn’t drop below 80 at night.

Usually I don’t add dechlorinator when I’m only topping it up a few inches-I’ve checked chlorine, nitrates and pH in the past, and haven’t needed to unless I’m adding a much larger amount of water. This is about 1800 gallons total with good aeration and gravel bog filtration system. But given the extremely hot weather coupled with about 20 goldfish that have grown quite large (6-8 inches) it may have been on the edge. I’ll check my water quality today and see if it has swung too far out of normal range. Thanks for the response.

Our pond goldfish, that we have had for several years we’re cheap feeders that started breeding last year. We now have babies of different sizes. Most are orange and white like the parents but a few we’re dark. Over the last week, one went blotchy, then completely orange. My bf thought I was crazy. He thought I was mistaken, but thanks for showing me I’m not! I know what my fishies look like lol

thanks for the information, I have 4 pond goldfish, cheap ones I saved in the 10 for $99cents from being fed to a snake or reptile. One is getting a big white spot, and another turned mostly white in the past week; I had a very dark pond and was treating for algae. All 4 seem active; so its a relief this is normal.

My goldfish, Scout, will be 8 years old this June. I won him at a carnival. A few weeks after I brought him home, he changed from silvery gold to orange. Then just the other week he started turning black. At first I was really worried until I read this article. Thank you for clearing that up for me!

Hi Destiny – Goldfish can change color for a variety of reasons. Color changes in goldfish are common as they age. Inexpensive goldfish, whose parents are unknown, can change in unpredictable ways while expensive show-quality fish will be a bit more predictable. Choosing fish foods that enhance their color will make them more vibrant. You can read a little more on the topic in this article: Why Do Koi (and Goldfish) Change Color?.

Generally, color changes in goldfish are common as they age. Inexpensive goldfish, whose parents are unknown, can change in unpredictable ways while expensive show-quality fish will be a bit more predictable. Choosing fish foods that enhance their color will make them more vibrant. You can read a little more on the topic if you hop over to one of our previous articles: http://wp.me/pgZB4-eA.

Hi Yami – Fish can change color due to a variety of reasons. During the winter, it can often happen due to stress from the environment. Often times their genetics play a big part in their developing colors. Their exposure, or lack of, to sun can cause a change in the intensity of their colors. Their fish food may be fine as a feed, however it may not contain the “extras” that brighten and maintain their color. Look for foods that contain color intensifiers and vitamins in them. Be sure to only feed your fish this high quality food when your water temperatures are above 50°. Here is another blog article that may help explain the color change: Why do Koi (and Goldfish) Change Color?

We have a small pond about 4 years old which has both Koi and Goldfish in the 8-14 inch range. Last year one of the goldfish completely lost all orange pigment throughout the season. It is a healthy fish , just changed color .